textproduct: Albany

WHAT HAS CHANGED

No significant changes to the previous forecast.

KEY MESSAGES

1) A low pressure system will bring rain and potentially some rumbles of thunder tonight, but no significant impacts are expected.

2) A Marginal Risk for Severe Thunderstorms is in place for much of the region tomorrow, though coverage of any thunderstorms will be isolated.

3) Temperatures are trending above normal for next week with increasing humidity. However, due to the potential for showers and thunderstorms, it is uncertain at this time how hot it will become.

DISCUSSION

KEY MESSAGE 1...

A low pressure system nestled in central Michigan will begin to track eastward beneath an upper-level shortwave this afternoon into this evening. Ahead of this system's warm front, an area of rain showers has taken shape and is tracking towards our region from western New York. Showers will initially remain largely within and north of the Capital District this afternoon into this evening before a secondary area of showers moves in tonight. This batch will become more widespread as the warm front lifts north and the upper trough moves overhead.

Lapse rates look to steepen overnight as a result of the shortwave's cold pool overspreading the region. Additionally, some weak, elevated instability looks to be present and intersect the best forcing for ascent. This will not only contribute to moderate rainfall rates at times, but the potential for some embedded rumbles of thunder. And, as this will be a fairly rapid frontal passage and pivot of the upper shortwave, there are no flooding concerns other than minor ponding in urban and poor drainage areas.

KEY MESSAGE 2...

Tomorrow, instability increases within the warm sector of the low as it tracks just to our north. 0-6km, line-normal bulk shear reaching 40-50 kt paired with ~500-800 MLCAPE suggests the potential for some organization of updrafts should there be enough forcing to initiate convective development. The uncertainty here pertains to whether or not the incoming cold front will be enough to really get things going in the afternoon, as the axis of the upper trough looks to race ahead of its passage. Deterministic CAMs seem to err on the side of very isolated coverage in even showers given this set up for tomorrow, so confidence is relatively high that thunderstorms will likewise be very isolated. The Storm Prediction Center maintained a Marginal Risk (Level 1 of 5) for much of the Capital District and areas to the east tomorrow with the greatest threat being strong to damaging wind gusts.

KEY MESSAGE 3...

A large-scale ridge continues to be depicted in the medium- to long-range guidance as extending into the Midwest off an upper- level anticyclone in the Deep South by Sunday night. As the high strengthens and shifts eastward next week, geopotential heights will rise and 850mb temperatures will increase to 1-2 STDEVs above normal through Saturday, July 4th. Surface temperatures are therefore expected to rise above normal with periods of southerly flow making for rather humid conditions. That said, several disturbances look to top the ridge through next week which may bring additional periods of showers and thunderstorms that would ultimately limit the extent of heat that we see across eastern New York and western New England. Additionally, guidance continues to suggest that the ridge never quite crests over our area, which will also limit the magnitude of heat that we experience next week. We will continue to monitor trends going forward and provide updates where possible.

AVIATION /00Z FRIDAY THROUGH TUESDAY/

Through 00Z/Saturday...area of light to moderate rain showers ahead of an approaching warm front will gradually move eastward across the region overnight. As the showers move through, VFR conditions may briefly become MVFR, mainly for Vsbys, with greatest chance for moderate rain generally occurring between 02Z-07Z/Fri, except a bit later at KPSF and KPOU. After the showers taper off, a period of MVFR/IFR conditions is expected, mainly for Cigs though some MVFR Vsbys will also be possible. Conditions should gradually improve to VFR between 13Z-15Z/Fri, with mainly VFR conditions in the afternoon. However, as a cold front crosses the region during the early to mid afternoon hours, isolated showers/thunderstorms will be possible through around 21Z/Fri. A brief period of MVFR/IFR Vsbys will be possible within any brief downpours.

Light/variable winds this evening will trend into the south to southeast at 4-8 KT after midnight, then south to southwest at similar speeds Friday morning. Winds will then shift into the west Friday afternoon behind the cold front at 5-10 KT. Winds will be stronger and variable in direction in and near any thunderstorms Friday afternoon.

Outlook...

Friday Night: Low Operational Impact. NO SIG WX. Saturday: Moderate Operational Impact. Chance of SHRA. Saturday Night: No Operational Impact. NO SIG WX. Sunday: No Operational Impact. NO SIG WX. Sunday Night: No Operational Impact. NO SIG WX. Monday: No Operational Impact. NO SIG WX. Monday Night: No Operational Impact. NO SIG WX. Tuesday: Low Operational Impact. Slight Chance of SHRA.

ALY WATCHES/WARNINGS/ADVISORIES

CT...None. NY...None. MA...None. VT...None.